Scientists have developed a way to grow living heart tissue – containing muscle and “blood vessels” – that beat rhythmically like a real heart on a microchip of sorts, called “AngioChip”. University of Toronto Professor Milica Radisic and her research team aim to use the technology to grow various kinds of “mini organs” that function the way real human tissues do inside the body, enabling them to be used for drug testing or even for replacements. “We can create artificial heart muscles in the lab and could potentially use it to replace the damaged tissue from the patient,” said Boyang Zhang, a PhD student in Radisic’s lab. Click here to view the first image in today’s viral picture gallery. Continue reading for the five most popular viral videos today, including one showing how people sent emails back in the ’80s.